The Endocrine System
Laszlo Vass, Ed.D. Version 42-0023-01-01
What is the purpose of this exercise? Are there any safety concerns associated with this exercise? If so, list what they are and what precautions should be taken.
Students will identify the major endocrine glands and tissues of the body. Students will relate each endocrine gland to the appropriate hormone. Students will explain how each hormone helps the body maintain homeostasis. Students will identify the histology of the major endocrine glands and relate it to their structure and function.
Exercise 1: The Pituitary Gland
Please describe in detail the structures and features you observed on the pituitary gland slide. Visible are the pars distalis (A), Pars intermedia (B) and the pars nervosa (C).
Data Table 1: Do some research and fill in the data table below.
Adrenocorticotropic hormone (ACTH)
| stimulates secretion of glucocorticoid steroid hormones from adrenal cortex cells
| Antidiuretic hormone (ADH)
stimulates water reabsorption
| Follicle stimulating hormone (FSH)
| regulates the development, growth, pubertal maturation, and reproductive processes
| Growth hormone (GH)
| stimulates growth/ cell reproduction and regeneration
| Luteinizing hormone (LH)
| In females triggers ovulation and development of the corpus luteum. In males it stimulates Leydig cell production of testosterone.
| Melanocyte stimulating hormone (MSH)
| stimulates the production and release of melanin in the skin and hair
Stimulates uterine contraction during childbirth, encourages mother-child bonding immediately after birth, and aids in the production and ejection of milk during breastfeeding.
| Prolactin (PRL)
| Stimulates the production of breast milk and breast enlargement to prepare for production of milk, sexual gratification.
| Thyroid stimulating hormone (TSH)
| stimulates the thyroid gland to produce thyroxine and then triiodothyronine, which stimulates the metabolism of nearly every tissue in the body.
A. Describe the function of the endocrine system.
The endocrine system secretes hormones into the bloodstream to maintain homeostasis within the body. The endocrine system is responsible for stimulating growth, sexual development, water reabsorption, uterine contraction during childbirth, maintaining electrolyte balance, and other major functions that keep the body’s balance on par.
B. What is a gland?
A gland is an organ within the body that synthesizes a substance, such as hormones, for release into the bloodstream (Endocrine) or to the body’s surface (Exocrine).
C. Describe how negative feedback regulates the secretion of most hormones. The negative feedback system regulates hormones by monitoring the level within the bloodstream. For example, if the Thyroid Hormone (TH) is high then Thyroid Stimulating Hormone (TSH) will remain moderate. However, if the levels of TH drop within the bloodstream, the level of TSH will rise to stimulate the thyroid to release more TH. This allows the body to keep the hormones near the set point necessary to maintain homeostasis.
D. Why is the pituitary gland called the “master endocrine gland”? The pituitary gland, which is controlled in large part by the hypothalamus of the brain, is responsible for secreting hormones that control or regulate the majority of the other endocrine glands within the body. For this reason, the pituitary gland is often known as the “Master” endocrine gland.
Exercise 2: The Thyroid Gland
Please describe in detail the structures and features you observed on the thyroid gland slide. Visible are the thyroid follicles (A), Colloid (B), and parafollicular cells (C).
A. What is the...
Please join StudyMode to read the full document